Line the casserole with the slices from one potato. In a large bowl combine remaining potato, zucchini, yellow squash, onion, basil, garlic, 3/4 cup of the cheese, Italian seasoning, salt, pepper, and eggs until well mixed. Arrange half of the tomato slices on top of the potatoes in the casserole. Evenly spoon vegetable mixture over tomatoes, pressing slightly to flatten. Arrange remaining tomato slices on top; sprinkle with remaining 1/4 cup of cheese. Bake 40 minutes or until vegetables are tender.